Cal. Code Regs. tit. 8, § 3914 – Required Inspections.

(a) Each amusement ride shall receive certification in writing by a registered engineer that it meets the requirements established by the Division.
Note: If the manufacturer of an amusement ride submits to the Division an accepted stress analysis for such ride certified by a registered engineer, the Division may, upon inspection of the ride, issue an original certification of inspection.
(b) The original certificate of inspection shall not be issued for any amusement ride until certification has been made and filed with the Division. The certificate of inspection and the certification will become void if the device is rebuilt or modified in a manner that will affect the structural design or strength.
(c) A registration number shall be obtained from the Division and will be issued with the original certificate of inspection and this number will remain in effect until the engineering certification is voided by modification.